soundproofed bonnet/hood

[paulr]

has anyone with normal operating temperatures( pagoda, not personally) had any experience of soundproofing under the bonnet / hood ? I am keen to do it but wary of revisiting the temperature gauge worry of years past.

paulr
lovely 1970 280 SL

[DavidBrough]

Hi Paul,

I used some under bonnet soundproofing material from these people www.noisekiller.co.uk whilst the car was quieter the outer portion began to peel and look unsightly after a while and I also felt it added to under bonnet temperature in summer. I have now removed it which was a job and a half but I am much happier now.

I also remember reading of someone that used a 107 pad from SLS but don’t know how they got on with it. On the basis of my experience I would say don’t bother.

I have made extensive use of other noise killer sound deadening products which are very good.



David Brough
1969 280SL Auto with A/C

[paulr]

Thanks David. In fact I was inspired by a post by you and it was Noisekiller that I was going to ask to do as least the boot and under the bonnet. I don't know that I mind so much what it looks like under the bonnet as I never really go there and it is the one thing that I think will do  most to make the cabin a bit less 'thin' I suppose. I rarely get the feeling that there is any padding in my car and as much a I like being in touch with it all, I would like a slightly woolier and fatter feel to the panels. Does that make sense?
I think I mentioned that I am also having the 3.27 axle put in and I have really got a bee in my bonnet ( no pun) about getting the car more comfortable sound wise.
Later, maybe next year I will have to have the floor replaced and I will have the inside very well proofed with new carpets and maybe rebuilt seats, but that is for next year.
So, given that I thankfully run cool I might give this Noisekiller a ring next week as I am having the axle done in time for a trip to France and would like to at least trial this pad before my 6 week trip to Amalfi in the summer. Did it really heat up underneath or was it more a cosmetic consideration?

Thanks for your comments. Sometimes it's just good to say things out loud, so to speak.

paulr
lovely 1970 280 SL

[Naj ✝︎]

Here's one from a pad from a W107:



naj

68 280SL

[paulr]

thanks NAJ. Is it effective? It certainly looks OK. Was there a lot of cutting to do? How about heat given that it isn't foiled?

paulr
lovely 1970 280 SL

[Naj ✝︎]

quote:Originally posted by paulr

thanks NAJ. Is it effective? It certainly looks OK. Was there a lot of cutting to do? How about heat given that it isn't foiled?

paulr
lovely 1970 280 SL

I made a newspaper template to cut the mat to size. It is used like this on the 107. It is a lot quieter now and I haven't noticed amy temp. rises but it has not been that hot since I installed it. I decided to do it while I had the bonnet off to change the oil cooler.

naj

68 280SL

[blue230sl]

i was interested in doing the same but in a thread about HOOD INSULATION PAD, mike salemi wrote:
I hear on good authority that you should NOT use a hood pad. The hood was made of aluminum specifically to dissapate heat; blocking the heat transfer is asking for trouble.

john
64 230sl euro 4 spd
89 190e 2.6

[blue230sl]

then again, i live in south carolina where temps in summer get into the 90s and low 100s; maybe your temp range will be more temperate, making heat dissipation less of an issue in the uk and northern europe...

john
64 230sl euro 4 spd
89 190e 2.6

[DavidBrough]

I think the problem with the noise killer under bonnet pad is the fact that it is silvered and reflects the heat back into the engine bay. I found things got quite hot at the front above the radiator which caused the silvering to come loose and look unsightly. It may well be that the black pads allow better heat transfer through the bonnet.

David Brough
1969 280SL Auto with A/C

[VivaDnA]

I installed a home made version using silvered neopreme cut to fit and mounted using an industrial strength spray-on contact cement.  The result:  Almost no noticeable improvement in sound insulation (even though neopreme is known for being VERY effective).  Also I haven't noticed any increase in operating temperature.  The bottom line for me is that it's been somewhat of a waste of time, although it looks pretty good.

[rwmastel]

quote:Originally posted by paulr

has anyone with normal operating temperatures( pagoda, not personally) had any experience of soundproofing under the bonnet / hood ? I am keen to do it but wary of revisiting the temperature gauge worry of years past.

Paul,
According to our Group's President, just sealing up the firewall will provide improved sound insulation.  Several pipes and wires go through the firewall and often the gap is larger than necessary.  New grommets or seals, or possibly home made improvements, can really quite down the cabin.

Rodd
Pagoda Technical Manual
please contibute: http://www.sl113.org/wiki/pmwiki.php
1966 230SL
2006 C230 Sport Sedan

[Naj ✝︎]

quote:Originally posted by paulr

For Naj

what did you use to secure the 107 pad to the hood? I have ordered one today from SLS.

paulr
lovely 1970 280 SL

68 280SL

[paulr]

update

The r107 soundproofing bonnet material is in and I'm not convinced it's made much difference, at least on it's own. I have ordered some "boom mat" for the interior which I will fit..sometime..which together with the hood may help. To be honest now that I have done the axle converstion it may all come together to have the desired effect.

quote:Originally posted by paulr

Thanks David. In fact I was inspired by a post by you and it was Noisekiller that I was going to ask to do as least the boot and under the bonnet. I don't know that I mind so much what it looks like under the bonnet as I never really go there and it is the one thing that I think will do  most to make the cabin a bit less 'thin' I suppose. I rarely get the feeling that there is any padding in my car and as much a I like being in touch with it all, I would like a slightly woolier and fatter feel to the panels. Does that make sense?
I think I mentioned that I am also having the 3.27 axle put in and I have really got a bee in my bonnet ( no pun) about getting the car more comfortable sound wise.
Later, maybe next year I will have to have the floor replaced and I will have the inside very well proofed with new carpets and maybe rebuilt seats, but that is for next year.
So, given that I thankfully run cool I might give this Noisekiller a ring next week as I am having the axle done in time for a trip to France and would like to at least trial this pad before my 6 week trip to Amalfi in the summer. Did it really heat up underneath or was it more a cosmetic consideration?

Thanks for your comments. Sometimes it's just good to say things out loud, so to speak.

paulr
lovely 1970 280 SL

paulr
lovely 1970 280 SL